mathewson



(NdMo-Ael.) 2 Sheets--Sh eet 1.

J. E. MATHEWSON.

FIGzB.

(N0 Medel.)

- A zsneetvsheet 2; J,- E. MATHEWSU a, SAND BLAST APPARATUW PatentedDec. 25, 1894.

NiTEn STATES JEREMIAH enemn mw cr, or SHEFFIELD, ENGLAND.

- 'sA'u cheer Arse-sari; s..

srncr warren remi s p r of setters eat- No. Enchanted December senses. 1

A-pplloatlon illed'I'ebrunry a, 1894, Ho; 499.482. is, model-l a wbb,whom; it may concern.- i

Be it known that I, JEREMIAH EUGENE MATHnwson, engineer,-of BellefieldWorks, Sheffield, in the county of York, England, 5 have inventedcertain new and useful Im-- provernents Relating 'to'Sand-Bla'st Appara-.tus, of which the following is a specification,

' Myinvention' relates to asa'nd blast apparates, which is employed inornamenting, cutto ting, orothe'rwise operating on various hard'surfaceannd'has for its object to improve 4 .the general constructionof the apparatus.

My invention consists first in arranging the fsandphoppeiwithin'aninclosin'g casing which "r 5 is filled with the fluid under pressurewhich.

serves as the propelling nredium,so that the sand will flow freely.

.. -Myinvention further consistsin providing.

a suitable plate or bracketyin the chamber .20 into which the sand flowsfrom the sand hop- .per, and which I call; the contactor combin- 1ugchamber, and from which the. propelling medium carries the. sand to theblast pipe through which it is thrown against the sur- ,z 5 fface to beornamented, the object of theplate N gbeing to insure that the sandsupply will be {driven by. the air blast from near the center j of thechamber and also to form a sand valve in a-manner to be explained. 0' Myfurther improvements will be pointed out in connection with thedescription of my invention, which is best explained by reference to theaccompanying drawings, in

'which.-'. 5 Figure, 1 shows in sectional elevation a ma- .chine fordelivering a horizontal blast, which is mostsuitable for metal, stone,and heavy work generally. Big. 2 shows asimilar view eta machipeferdelivering blast upwar 49 this being the form most suitable for glassand light work, and Fig. 3 is a View taken on v a sectionline at rightangles to;that taken in Fig. 1, showing the lower part of the sandhopper and the combining chamber below it 4 5 Referring first to theconstruction shown in Figs. 1 and. 3, which relates to whatI term thehorizontal blast apparatus, A is a casing, preferably cylindrical, whichis divided into .two compartments or chambers 1, 2, by the I '50partition 18; This partition B, as shown, has

an opening or openings closed by a suitable valve or valves, as G, topermit from time to timeiof'thedisch arge of sand from com ngment 1 tocompartment 2. InyFig. 1 I- have showna disk valve' carried bye springactuated rod L for controlling this opening,

*In compartment 2, which .is made airtight,

except for the inlet and outlet cpen'iugs, is placed asand hopper A,which is conven i-ently supported on a casting D resting on or supportedfrom the bottom ofthe casing A.

With this casting D is formed. what l'ierm. I the-jcoinbining-or contactchamber DI, since it"is here at the sand and the propelling inedinm rstcombine or come in contach's The 'sand'passes fromthe hopper A to thechamber D bye passage c in the casting D, whichcan bs-opened or closed,as required, from the outside by a suitable valve E.- l I F.=isthehinletier.the prepell ng. manners which is scmefluid, as air, steam,dvc.,-duder pressure, and, as will'be noted, this fluid fills thecompartment 2 so that there will \be the same pressure on the top of thesandi'n the' hopperA as at the discharge passage lead- 7 5 ing into thechamber D so that the sand can 'fiow t'reely-fz'om the hopper bygravity, en-

tirely uniniluenced by the pressure of thepropelling medium. "I prefer,as shown, to provide anopening, as indicated at d, from the compartment2- into the combining chamber D, though of course the fluid underpressure could be introduced therein through any suitable conduitdesired. 3 D is-a plate entowhreh the-sand falls from 8 the sand hopper,and the object of this plate, which is arranged about the middle of thetube, which serves as the contact chamber in Fig. l, is to keep the sandsupply in the'cens ter of the contact chamber D' so as to insure go itsbeing properly carried forward by the propolling fluid. The plate Dfurther serves to form a sand valve when the apparatus is not beingused. The sand falls on this plate and terms a little cone of sandwhose-apex finally o5 closes the sandpassage which'leads from thehopper. It the plate were not employed the bining or contact chamber D,when neces m: in Hmmmmmompmtment,'

in Figm 1 mad 2.

1:) k '1. In a mud blast appamws the cbmbfna- 5 fiipu 01?. a wmpm'tmem;01f chamber 3, a sand Mppm situated fihemin gm inlet into saidmagnumfor: a suitable compressed propelling m'wflium, eomhiuing oraun'taahchamber be mat-him mm hup gwr, an. passage fur the flow' 01: MMfmm mid hupper t0 the contact chain 1; 3:) 151m mm an iniet thamw forthe propelling" medium. mud a mm for eonvaying awaythg mud driven byfilm propelling meflilzam. H T" fi. 3m mmrl' blmmfiappmsmufi, theeombirm 4 s'a'nere' I 3 tion 01 an air tight compartmentlor chamber 2,a. sand hoppe'nsitueted therein, an inlet into said chamber fore;suitable compressed propelling medium, a. "combining of contact 5chamber beneath the send hopper, a passage: vfor the fiowot sand fromsaid hopper to the] coniact chamber, an inlet for the propelling mediumfrom the chamber 2 to the combining chamber, and an'ontlet from saidcombining 10131121111116! for the mixed send and propelling medium. f 3;In a sand blast apparatus, thecombinetion of a sand hopper, acombiningor contat' chamber into which-the sand fiows f'rom the. r5-hoppen-en inlet to said chamber for. fluid under pressure, a flexiblepipe G'mf the same crosssection as the combining chamber, lead ingtherefrom, and serui'ngj to conduct away. .the propelling medium mixedwith sand, and 2s a. blast "pipe Hjof -reduced cross section sirrangedon the end of the flexible pipe G' whereby the sand may havescomparatively slowiinotion in the flexible pipe andet'tai'n'" itsmeximumvelocity only in the blestpipe. 4, In e'send blast-apparatus, thecombine- I tion with a sand hopper, ot a combining or contact cha mberinto which sand flows fromthehopper, an inlet thereto for fluid tinderpressure, a tube or pipe G leadinggfron'i said chnmbenie blast pipe-Hotreduced sizeon the end ofthe tubc,' cnd nn-outwerdly iiering tube Jontheend ofthe blast pipe, substam tially for the'pnrposespeeified. r

, j 5.. In a. sand blast apparatus, the combine- 3 tion of a sandhopper, eeombining orcontaet chamber into which thesand' flows from theT hopper, an inlet to'said chamber forfluid-under pressure, e flexiblepipe Q of the same crosssection. as the combining chamber leadingtherefrom and serving :toconduct'ewhy the propelling medium mixed withsend, a blast pipe H ofreduced cross-section zirrangedon the end oil thefiexiblepipe G, and e flaring pipe or tube J, into whichiheblast pipe H5 opens,whereby the sand meyhave a coinperatively slow motionin ,the'flexible tube end attain its mnximnm-jvelocity in the vblast pipe, endso that the propelling medium may have BA'OhfiHCG to expend afterleavingthe 5o blast pipe.

ii -e ,send blast zipper-ates, the combine: tionoii a's'end hopper, acombining or contact chem'beri-nto which the sand flows from the m PP aninlet for fluid under pressure 1 20 said combining or contact chamberand-e, "Fle platform, D in said chamberinto which the sand flows fromthe hopper.

'37. In a sand blast apparatus, a box or casing A divided intotwocompertments 1. end-.2193; a suitable partition, a sand hopperin theup--=ee *pefcompertment 1, a. valved opening inihe partition wherebysend can be supplied to the sand hopper, cn'inlet for fluid underpressure' leading into the'iowermost compattmentf ii contact orcombining chamber underneath the hoppenen inlet trorn'th'e compartment,2;

to the combining chamber and a blastipip'e leadingthe'refroin. 8."In esend blast apparettis "the eomhine-' tion with a suitable casing havingan openin'gi 7Q" .1, of a; seed hopper est-A da said casing below theopening 12h pipeL'leeding from the casing outside of the hopper A, meansfor erecting a. current of air through the casing and out at thetube L,and a send blast pipe. 7

adapted tdthrow e'streem of sand against an object held overthe opening1, all substantially as specified, and so that the fine dust and brokensandw'ill be separated from the unbroken sand and carried out of "thecasing while the unbroken sandwill fell'into and be collected in thehopper A 9, In it send blcst'sppe'retu's the combine Hon-with en (sirtight casing or compartment, 2 to which fluid under pressure issupplied, 8

of-e receptecle for sand situated therein, a, combining or contactchamber below the receptacle, a passage for the flow of sand from saidhopper to the contact chamber, a sec-.-

0nd chamber 1 through which the sand blast passes, a pipe openingfrom'the chamber 1 an ejector ada. ted to creete a current of air

